Today, in processing systems it is common practice to have dampers for a piston pump. By having the dampers the pressure peaks formed when the pistons are moving back and forth are reduced and hence the negative effects for the homogenizer as well as other parts of the systems can be reduced.
One common type of pulsation dampers used in this field is partly air filled upright tubes placed upstream and downstream the piston pump. In short, when a pressure peak arises the air is compressed, thereby resulting in a damping effect. One disadvantage of this design is that it is most often cleaned manually since the air filled upright tube constitutes a dead end and hence is difficult to clean automatically using cleaning in place (CIP) procedures.
Another disadvantage is that the air will be consumed over time due to that the air is dissolved in a liquid product being processed. Thus, also for this reason, this kind of pulsation dampers needs to be filled with air from time to time.
In U.S. Pat. No. 7,278,837 it is suggested to connect the two pulsation dampers with each other via a tube provided with a shut off valve. Thanks to the tube connecting the two pulsation dampers the pulsation dampers may be cleaned automatically.
Another type of pulsation damper is described in GB 2 129 876. The pulsation damper consists essentially of a centre zone with non-circular sections so that it may flex under pressure towards a circular section and resiliently expand to absorb the pulsations.
Although different types of pulsation dampers have been developed there is still a need for cost efficient damper solutions providing for efficient damping, robust design, secured hygiene and low total cost of ownership.